On 10/2/18 9:58 AM, Vladimir Sementsov-Ogievskiy wrote:
-# @device: device name to set latency histogram for.
+# @device: device name to set latency histogram for (better use @id).
+#
+# @id: The name or QOM path of the guest device.
Hm. It all looks a bit weird. I've just duplicated block_set_io_throttle
interface:
But that interface was pre-existing under a stable name, so it had to
worry about back-compat. Here, we are adding a new command, so we don't
have to be stuck with back-compat ugliness.
# @device: Block device name (deprecated, use @id instead)
#
# @id: The name or QOM path of the guest device (since: 2.8)
blk = qmp_get_blk(arg->has_device ? arg->device : NULL,
arg->has_id ? arg->id : NULL,
errp);
if (!blk) {
return;
}
So, looks like "The name or" is wrong part. @id can be only path.
However, I can call blk_by_name on @id, if blk_by_qdev_id failed..
So, variants:
1. both parameters, current code, but fix documentation (will be @id:
QOM path of the guest device.)
2. only @id and only QOM path
3. only @id, but fullback to blk_by_name(@id) if failed to find qdev.
Any option is ok for me, I don't care. What do you think?
I'm leaning towards 3.
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3266
Virtualization: qemu.org | libvirt.org
